Method of and means for quadruplexing cables.



I. KITSEE.

METHOD'OF AND MEANS FOR QUADRUPLEXING CABLES. APPLICATION FILED AUG-2, I911- RENEWED nsc. 30. ms.

2 shins-shin l- 1 ,21 9, 1 1 0. I atented Mar. 13, 1917.

WITNESSES.-

I. KITSEE.

METHOD OF AND' MEANS FOR QUADR-UPLE XING CABLES. APPLICATION FILED AUG-2.191! RENEWED DEC. at, 1916.

1,21 9,1 10. Patented Mar. 13, 1917.

2 SHEETS-SHEET 2- WITNESSES.-

INVENTOR.

'm: nan-ms FIYEIS m. INdm-Lhn l. wunmcmu. n c

polarity.

' Whereas in UNITED STATES PATENT oEEIcE.

IsIIioR. KI'ISEE, or PHILADELPHIA, PENNSYLVANIA, ASSIGNOR'LB'Y. MESNE ASSIGN- M'ENTS, T0 AMERICAN TELEPHONE AND TELEGRAPH COMPANY, OF NEW YORK,

N. Y., A CORPORATION 01 NEW YORK.

METHOD OF AND MEANS FOR QUADRUPLEXING CABLES.

Specification of Letters Patent.

PEUJGIltGd Mar. 13, 1917.

Application filed August 2, 1911, Serial No. 641,933. Renewed. December 30. 1916. Serial No. 139,963.

To all whom it may concern:

Be it known that I, Isioon KI'rsEE, citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Methods of and Means for Quadruplexing Cables, of

. which" the followin is a specification.

After long and careful experiments, Iv

have found that the system as will hereinafter he described is well adapted for the purpose of quadruplexing messages over lines with great capacity, such for instance as submarine cables.

I have'found by actual experiments on a submarine cable that if true reversals are impressed-upon the cable, a greater number of pulses can be taken care of by the receiving instrument than when pulses are trans. mitted, as 1s today the case, deslgnatmg characters, for the reason. that the grouping of such characters in the telegraphlc alpha h bet requires very often the impressing upon the line of two or more pulses of like I The reater cfficiency of true reversals was to e expected, but, in my experiments on a submarine cable, I have found that actual telegraphy with the double key, the speed one. particular cable was limited to two hundred and forty letters per minute requiring-by actual count-somewhat less than five hundred pulses, the same receiving instrument gave perfect results when nine hundred pulses of llzrue reversals were transmitted over the me. I

In, the drawing, Figure 1 is a diagram matic View of a transmitting device used in and adapted to be revolved'by any suitable means. Each of said parts is provided with the conducting seg ments 5 and the noncon ducting segments All of the conducting segments 5 are i1 electrical contact with each other. The sa me is true of the conducting segments 5 of thecommutating'part b. In reality, the corn nutatin-g wheel 4 may be constructed of two metallicwheels having cut out portions filled with nonconducting material. 7 and 8: .re two brushes, one brush in contact with the part a of the commutating device and the second brush in contact with the part b of the commutating device. A and B are two transmitting organisms. The organism A c'n'nprises here the key 12 connected with the interposition of the battery 9 to the coil cf electromagnet 10. The armature 11 of said electromagnet is held upward by the sprf ng 1.8 and is connected to the brush 8 of the commutating part a. 13 and 1.41 are two sources of current. source 13 is here shown as to consist of twenty-five cells and the source 141 is here shown as to consist of five cells. Both sources are grounded with their negative poles at 15. The positive pole of the source 13 isconnected to the stationary contact 16 and the positive p'cle of the source 14 is connected to the stationary contact 17. I

Normally, that is when the key 12 is open, the armature 11 rests against the contact 16 of the source of current 13. The or anism B comprisesthe'keylfl connected wlth the interposition of. the battery!) to thecoilof. electromagnet 10 The armature 11 of this electromagnet is h :ld upward by the spring 18 and is conneci ed to the brush 7 of thev commutating part b. 13? and 14* are two sources of current connected with their positive poles to the g1 011ml 15. The source 13 is here also shown as to consist of twenty The fiv'e cells and the source 1 1" as to consist of five cells. The negative pole of 13 is connected to the stationary contact 16 and the negative pole of the source 14 is connected to the stationary contact 17 Normally, the armature 11 rests against the contact 16 of the source 13".

I will now describe the function of this part of my invention.

The commutating device 4 is revolved at the required speed and the cable 1 will, therefore, alternately connect through brushes 2 and 3 with the conducting segments of the commutating part a and the conducting segments of the commutating part 6. Normally, that is when the keys of both of the stations A and B are at rest or open, the source 13 of the organism A will connect with its positive pole through brush 8 with the conducting segments of a and the source l3 will connect through its brush 7 with the conducting segments of b, when such segments are in alinement with their respec tive brushes, and as the commutating device is always revolving, it is obvious that the sources 13 and 13 are alternately connected with the cable 1 and that, therefore, -alternate impulses of the same duration and practically the same intensity are impressed upon said cable. Such alternation of pulses Icall true reversals. In my system, therefore, true reversals are transmitted over the line when all transmitting organisms are at rest.

It is now supposed that the operator at A depresses his key thereby energizing his electromagnet 10. This operation results therein that the armature 11 is drawn down ward and away from the contact 16 and in contact with 17 The connection of the battery 13 with the cable is, therefore, broken and the connection of the cable through the segments of the commutating device made with the battery 14.

The sequence of true reversals will, therefore, be interrupted or changed. A strong negative current from the organism B will alternate with a weak positive cur rent from the organism A.

It should be understood that the force of 13 or 13 is sufficient to actuate its own receiving device at the far end of the cable, but the force of 14 or 14 is insuflicient to operate its receiving instrument but suflices to clear the cable.

As long as the key 12 of organism A re? mains depressed, the sequence of strong negative and weak positive impulses will remain, but as soon as this key is open, true reversals will again be impressed upon the cable. When the key 12 of station B, is-depressed, the connection of the battery 13 with the cable through the segments of the commutating part b is interrupted and the connection of the battery 14: with the cable through said segments is established. The sequence of the true reversals is again interrupted or changed, but this time a positive pulse of high intensity alternates with a negative pulse of low intensity, or in other words, the former orderin now reversed.

It is now supposed that both, the key 12 of station A and the key 12 of station B are simultaneously closed. The connection of the battery 13 as well as the battery 13 with the cable through the respective segments is interrupted, but the connection with the batteries 14 and l4: is established and, therefore, reversals of low intensity will be impressed upon the cable. These pulses of low intensity will not affect the receiving instruments at the .far off station.

In placing into practice the organism as described, the following rules have to be observed The higher the speed of the commutating device, the more efiicient the system, but the speed should only be quick enough to allow asuccession of pulses not quicker than the cable and receiving devices inserted at the far end of same are capable of taking care of; and the number of signaling characters produced by the operation of the key of each transmitting organism should be less than the number of pulses impressed as true reversals upon the line from that particular transmitting organism.

I have in this drawing referred to the different signal batteries as to consist of twenty five individual cells, but it is obvious that the number of these cells may be changed in accordance with requirements. I have also illustrated the-what I call clearin cells as to'consist of one fifth of the num er of the signaling cells, but it is also obvious that this ratio may differ.

The reason why this system provides for the so-called clearing cells is, that should only one message be transmitted for a comparatively long time over the cable and, therefore, one polarity be depressed for such length of time, the cable would, as it is technically called, choke. The accumulation of the current of one impulse due to the great capacity of the cable would be such as to make the signaling nearly, if not quite, impossible.

In actual practice, I have found that a small current of a polarity opposite to the signaling current suflices to obviate this difficulty. In this system. therefore, the following method is employed 1st:No operator signaling. In this instance, true reversals are impressed upon the line and received as such at the far off station, thereby actuating there the receiving device operatively related to the transmitting station A and the receiving device operatively related to the transmitting station B.

Normally, therefore, at the receivin station, both instruments will be actuate and comes to rest, this vibration will again com- 3rd :When the operator at B transmits a message, he depresses his own signaling current and the receiving device adapted to be operated by this current will cease its vibration and will come to rest.

4th :When both, the operator at A and B, simultaneously transmit signals, then both signaling currents are depressed and at the far ofl station, both receiving devices 1 come to rest.

In Fig. 2; 19 and 19 are two receiving devices here illustrated in conventional sign as two moving coils. Different types of receiving devices may be employed as long as thesensitiveness and correctness of same meet requirements. The coils, as illustrated, may represent the coils of the Well known siphon recorder used today in cable work. In such case, one of the connecting fibers should be placed out of service, so that the coil, in its movement, should only be able to affect the movement of the contacting device in one direction. These contacting devices are here shown as conducting strips or rods provided with contacts at their ends and are designated by the numerals 20 and 20", respectively. The cradle with its suspension is designated by the numerals 21 and 21", respectively.

It has to be borne in mind that the siphon of the usual recorder and the contact arms substituted therefor, have a normal position and will always return to this position after the effect of the signaling current has died nect to an outside circuit the conducting strip or rod 20; and 25 the means to connect to an outside circuit the conducting strip orjrod 20. I

The long unfeathered arrow illustrates the direction in which the coil of the device 19 is supposed to move through the impression upon the line of a positive pulse and the small. unfeathered arrow indicates the direction in which the-conducting rod 20 is supposed to :nove through the deflection of the coil of the device 19. The long feathered arrow indicates the direction in which the coil of tie device 19* is supposed to move through the impression upon the line of a negative pulse; and the small feathered. arrow indicates the direction in which the conducting rod 20 is supposed to move through the deflection of the coil of device 19*.

In Fig. 3, which, as stated above, illustrates one terminal of a cable embodying my system of quadruplexing said cable, 1 is part of the cable. 26, 2(, are the two bridge arms as usually employ ed in duplexing cables;

27 27, are the cross wires of the bridge; to

these cross wires is here shown to be connected the impedance 28. For the purpose of practisingmy invention, this impedance is not-necessary, but the same is placed here in shunt to the receiving organism later on to be described, as it was found that through such impedances the incoming impulses are sharpened and m: Ly, therefore, be better adapted to produce desired results. In shunt to this impedance are positioned the receiving devices 19 and 19 with their respective armatures or connecting rods 20 and 20*; and in juxtaposition to these armatures or connecting rods is placed the movable contacting de ice 22 with the shaft 23.

and the contacting brush 24. To the connecting rods or arr iatures are connected the wires 25 and 25". This part of the system is clearly illustratt d in Fig. 2. .29 and 29 are two electroma gnets preferably of the neutral type. The coil of electromagnet 29 is connected with one terminal towire 25 and with the other terminal with the interposition of the source of current 30 to the brush 24. The coil of electromagnet 29 is connected with one terminal to wire 25 and with the other terminal, with the interposition of the source of current 31 to the brush 24. The armature 32 of electromagnet 29 is provided with the two stops 33 and34, and

a is normally held against the stop 34".by suitable means here sh )wn as the spring 35. 36 is a converter or iaductorium, the primary thereof connected with the interposition of the source 37 to the stop 34 and armature 32,

respectively; the secondary of this converter or inductorium is connected to the polarized relay 39. In the circuit of this polarized relay are here shown the impedances 40, the purpose of which will be later on described. 41 is the armature of the polarized relay provided with the stops 42 and 43. 44 is a translating device here shown as a sounder and this translating device is connected with the interpositioncf the source 45 to the armature 41 and s1 op 43, respectively. The:

whole organism is designated by the letter A corresponding with its transmitting station A.

The arrangement of the second receiving organism is a duplicate of the arrangement of the organism just described and similar parts are designated by similar numerals with the exception that the letter 6 is added to these designations. This second organism, as an entirety, is designated by the letter B corresponding with its transmitting station E.

It has to be added that the polarized relay of each organism is provided with a reset circuit here shown as to consist of the wires 46, 46, source 47 and key 48.

As was clearly stated in the description of Fig. 2, the armature'or connecting rods of the receiving devices 19 and 19 have their own zero position, that is, if the armatures are deflected through the movement of the coils, they return to their normal position when the movement of the coils ceases. Should, therefore, no pulses be impressed upon the line, then the armatures 20 and 20 ofthe receiving devices will remain at their zero position. This zero position is indicated by a full and unbroken line.

, When an impulse is transmitted over the line adapted to actuate the coilsayof device 19, then its armature will move in a direction as indicated by the dotted lines and Will, therefore, connect with the revolvingcontacting device 22; and when the impulse impressed upon the line is such as to actuate the coil of the device 19', then its armature 20 will move in a direction as indicated by the dotted lines and connect with the revolving contacting device 22.

As now in my system, normally, that is, when the keys at both transmitting stations are at rest, true reversals are transmitted from these stations in quick succession, it is obvious that the armatures 20. and 20 will alternately be moved from their respective zero positions in a direction toward and in contact with the device 22.

I will now describe the effect of this vibratory movement of the armatures of the receiving devices and I will take for this description the organism as illustrated at A, it being understood that the organism as illustrated at B is a duplicate thereof.

As long as the armature 20 of the receiving device 19 is at its zero position, that is, out of contact with the device 22, the circuit including the localized electromagnet 29 is open and its armature drawn by the spring toward and in contact with stop 34 will re main there and a circuit including the primary of the inductorium 36 is made. No current, therefore, will be generated in the secondary and the polarized device 39 will remain unaffected; its armature, which is unbiased, will, therefore, remain at that stop impulse has driven the armature to the stop where the last impulse has driven it. If this stop is the one connected to the circuit of the translating device 44, then the translating device will be actuated, but if the last 42, then the circuit including the translating device will remain open.

It is now supposed that true reversals are impressed upon the line from the transmitting station; and it is supposed that the receiving device 19 is actuated by positive pulses transmitted from the station A. The armature 20 of this receiving device 19 will, therefore, be brought in contact with the connecting device 22 as often as positive pulses are impressed upon the line; and as these reversals follow in quick succession, it is also obvious that the armature 20 will alternately connect and break the connection with the device 22. .The making of this connection will close the circuit including the electromagnet 29 and the breaking of this connection will open the circuit including this electromagnet. The armature 32 of the electromagnet 29 will vibrate in unison with the vibration of the armature 20 of the device 19 and will alternately connect with the stop 34 and break this connection, thereby alternately making and breaking the circuit including the primary of the inductorium 36.

It is now supposed that the making of this circuit will induce in the secondary of the inductorium an impulse adapted to drive the armature 41 of the polarized device 39 toward and in contact with the stop 43 of this device; and it is supposed that the breaking of the circuit including the primary of the inductorium 36 will induce in the secondary an impulse adapted to drive the armature 41 of the device 39 in a direction opposite to the former movement, that is, in the direction of the stop 42.

It will, therefore, be seen that the vibratory movements of the armature 32 of the device 29 are reproduced in the vibratory 11o movements of the armature 41 of the device 39.

The circuit including the device 44 and the device itself are so conditioned that it requires a good contact of a predetermined length of, time between the armature 41 and the stop 43 of the device 39 to actuate this translating device and it is taken for granted that the vibrations of the armature of 39 are of such short duration, starting from the resting place of stop 42, that this armature either does not touch at all the stop 43 or remains there for a time insufiicient to produce the required good contact. The translating device 44 will, therefore, remain unafi'ected during such vibrations.

The circuit connecting the secondary of the inductorium 36 with the polarized relay 39 is provided with means so as to produce the necessary lag and these means are here l latin en, w now, the key at the transmitting station A and the key at the transmitting manner,a short time todenote a dot and a longtimeto denote a dash. The depression of the key of the transmitting station A will disconnect the positive signaling current from the cable and only negative slgnaling pulses will be transmitted alternating with weak clearing pulses. The device 19,

. therefore, will not be actuated and its armature 20 will come to rest at its zero position and will remain there as long as the key at the transmitting station -A remains depressed. The circuit including the electromagnet 29 will, therefore, remain broken for. the same length of time and the armature 32 will remain during this time at the stop 34, closing the circuit including theprimary of the inductorium. This operation will generate in the secondary a pulse adapted to drive the armature 41 ofthe de-- vice 39 toward and incontact with stop 43 v and, asno other pulse will-follow, the armature will remain there for a time sufiicient to actuate the translating device 44. But as soon as the key of the transmitting station A .is opened, the positive signaling currents will be impressed upon the line and the vibration of the armature 20 of device 19 will commence, thereby making inoperative the translating device 44.

Itwill, therefore, be seen that thelength of o eration of the device 44 will always coinci e with the length of time that the key p 12 of transmitting station A is depressed.

When the operator at B desires to transmit messages, he depresses his key in the usual manner. Through the depression of this key, .the connection of the cable with the negative signalin current is broken and the armature 20 of t e device 19 will come to rest at the zero position and will cease its vibrations. The vibrations of the armature 32 will cease and its effect on the armature 41 of the device 39" are the same as the andthe armature 41 and thistime, the transdevice 44 will answer.

station 13 are simultaneously depressed, then the connection of the positive signaling cur rent as well asthe connection of the negative signaling current with the cable is broken. Both of the armatures2O as well as 20 will ceasetheir vibrations and the effect of the ceasing of the vibrations of both armatures will be that the ar'matures of 29 and 29* will come to rest at their respective stops 34 and 34" and will actuate the armatures 41 and 41", in a manner so that both the translating device 44 as Well as the translating device care should be taken that the different circuits in the receivin Er organism areso condi' tioned and arranged that the short closing periods of the arma aures of the receiving devices inserted in the cable shouldv not be suflicientto actuate the translating device, but that the time'unit to make a dot at the transmitting statioi. should sufiiceto actuate the translatlng dev: ce.

1n m'actice, the impedances 40 may be such value so as to e atirely depress the vibrations of the armature 41 of the device 39 as long as the vibrations of the armature 32 of the device 34 follow each other in quick succession.

When forone res son or the other the system is to be out 01 commission for a comparatively long time, say for hours, and when the transmittng operator has notified the receiving operator to this effect and when the armature 41' is resting against 43, after the notification of the transmitting operator that he has taken ofi entirely the transmitting organism, then it would only be a waste of current and uncesirable that the circuit including the translating device should remain closed; and to obviate this disadvantage, each of the polarized devices 39 as well as 59 is provided with the shunt circuit 46, 46, as above described.

When the receii ing operator desires to drive thearmature 41 from the stop 43 toward and in contact with 42, he depresses the key 48 for a, short period and itis sup posed that the CIII'I ent from 47 will actuate the relay in a man: ier so as to produce this effect.

Thequestion may be raised if the effects as outlined could not be produced by an arrangement by which the armatures 20 and 20 of the devices 11) and 19 are normally in contact with the device 22 and are brought out of contact through the impressed impullses on the cable. affecting their respective e01 s.

No doubt, similar eflects, as above outlined, may be produced with such arrangement but it was considered more beneficial in practical work t) use the arrangement as note that no message is transmitted, reducing but not interrupting the positive pulse of said reversals to denote that one message is transmitted, reducing the negative pulse of said reversals to denote that a second message is transmitted, and reducing the electromotive force of both polarities of said reversals to denote that two messages are simultaneously transmitted.

2. In a system of quadruplex telegraphy, a line of transmission, means for each terminal of said line to normally impress thereon reversals, means for one station of each terminal to depress the positive pulses of said reversals, means for the second lation of each terminal to depress the negative pulses of said reversals, two receiving devices for each terminal, a local circuit for each device of each terminal, both devices at each terminal alternately making and breaking said local circuit in quick succession through the transmission of said reversals, an electromagnet for each local circuit 01": said devices, a translating device operatively related to each of said electromagnets and means whereby each of said translating devices is silent as long as its receiving device is operative and means for each of said translating devices to make the same operative as soon as its receiving device becomes silent.

3. Inquadruplex telegraphy, a line of transmission, two transmitting stations for each terminal of the line, a source of current for each of said stations, means to normally connect said source of current to said line of transmission, means for eachof said stations to reduce but not interrupt the electromotive force of said source of current, and means'to connect one or the other of said sources alternately to the line.

4. In quadruplexing lines with distributed capacity, two receiving stations for each terminal of the line, one. station of each terminal provided with a receiving device adapted to be actuated by a positive current, the second station of each terminal provided with a receiving device adapted to be actuated by a negative current, an armature for each of said receiving devices, a COIl-v tacting device in juxtaposition to the armatures of the receiving devices of each station, a local circuit for each of said armatures, a source of current and electromagnet in each local circuit, an armature for each of said electromagnets, a translating device in operative relation to each of said armatures and means to make the translating device operative through the inoperativeness of the armature of its electromagnet and make said translating device inoperative during of transmission, a localized relay operatively related to said line relay and means for said localized relay to generate locally pulses of alternate direction in accordance with the movement of the movable part of the line relay.

6. In quadruplex telegraphy, a line relay for each receiving station, a localized polar relay for each of said line relays, and means for each polar relay operatively related 'to the line relay to vibrate each of said polar relays in quick succession to denote that no message is received and to cease said vibrations for each polar relay todenote that two messages are received simultaneously.

7. In telegraphy, in combination, a line instrument, an electromagnet adapted to be operated by said line instrument, an electric circuitfor said electromagnet, a second electromagnet in operative relation to said electric circuit and retarding means to produce a lag of the flow of the current through said second electromagnet.

8. The method of receiving signals in 'quadruplex telegraphy, which consists in causing at each receiving station the development of rapidly recurring impulses to denote that no message is received, causing the dequadruplex telegraphy, which consists incausing the development at each receiving station of rapidly recurring impulses to denote that no message is received, the impulses for the two stations being of opposite polarity, and causing the development of such impulses to cease at both stations to denote that two messages are simultaneously received.

10. The method of receiving signals in quadruplex telegraphy, which consists in causing the development at each receiving station of rapidly recurring impulses to denote that no message is received, said impulses at the two stations being of opposite polarity, causing the development of such impulses to cease at one station to denote that one message is received, and causing the development of such impulses at both stations to cease to denote that two messages are simultaneously received.

11. As an improvement in the art oftransmitting a plurality of signals over a line or cable, the method which'consists in normally impressing upon the line or cable impulses of substantially equal strengths alternating in polarity, and simultaneously reducing the impulses of both polarities to lower and substantially equal strengths to simultane- 1 ously transmit two signals;

12. As an improvement in the art of simulreducing the strength of the impulses of the taneously transmitting a plurality of sigother polarity to represent anot er signal. nals over a line or cable, the method which In testimon whereof I affix my signature consists in normally impressing upon the in presence of two witnesses. line or cable successive impulses of substan- ISIDOR KITSEE. tially equal strengths and alternating in Witnesses: polarity, reducing the strength of impulses EDITH R. STILLEY, of one polarity to represent one signal, and MARY C, SMITH.

coplel of this patent may be obtained for five cents each, by address! mg the Commissioner of Patents, Washington, D. G. 

